<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>sessionStorage</title>
</head>
<body>
    <h2>sessionStorage</h2>
    <button onclick="saveData()">点我保存一个数据</button>
    <button onclick="readData()">点我读取一个数据</button>
    <button onclick="deleteData()">点我删除一个数据</button>
    <button onclick="deleteAllData()">点我清空数据</button>


    <script>
        let p = {
            name: '张三',
            age: 18
        }
        function saveData () {
           sessionStorage.setItem('msg', 'hello!')
           sessionStorage.setItem('msg2', 666)
           sessionStorage.setItem('person', JSON.stringify(p))
        }
        function readData () {
            console.log(sessionStorage.getItem('msg'))
            console.log(sessionStorage.getItem('msg2'))
            console.log(JSON.parse(sessionStorage.getItem('msg2')))

            console.log(sessionStorage.getItem('msg3'))
        }
        function deleteData () {
           sessionStorage.removeItem('msg')
        }
        function deleteAllData () {
           sessionStorage.clear()
        }
    </script>
</body>
</html>